Try to run injector tests with popular DI containers

[samdark]

To ensure Injector is fine with popular container it is a good idea to run tests against:

1. yiisoft/di
2. php-di
3. league container

Likely it won't reveal any issues but worth checking.

[roxblnfk]

I've been using Injector in production with php-di for almost a year now. Works great.

[samdark]

That's good but I think we can try running tests against real containers. At least in a separate branch.